Many diesel engines have hydraulically activated and electronically controlled fuel injection systems. In these systems, a microprocessor sends a control signal to trigger electric current pulses to the fuel injectors. At the start of an injection cycle, the electric current pulse energizes a solenoid to operate a valve in the fuel injector. The valve opens an hydraulic conduit letting high-pressure hydraulic fluid operate an intensifier piston. Operation of the intensifier piston causes the injector to inject fuel into the cylinder.
At the end of the injection cycle, the microprocessor stops the electric current pulse. As the solenoid de-energizes, the valve returns to its position at the start of the cycle. This action enables the valve to open the drain on the fuel injector, thus draining hydraulic fluid out of the injector. The loss of hydraulic fluid enables the intensifier piston to return to its position at the start of the cycle.
When hydraulic fluid is released by the fuel injector, the fluid drains out of a drain on the side of the injector. The "spring back" of the intensifier piston causes hydraulic fluid to spray or spurt out of the drain. If not deflected upon its exit from the injector, the hydraulic fluid will turn into a mist. The misted hydraulic fluid will mix with air and vent outside the engine.
To prevent misting of hydraulic fluid from the fuel injector, deflectors are mounted on or near the fuel injectors. Some designs bolt a deflector onto the injector or other part of the engine. Other designs provide a series of connected deflectors or a deflector rail similarly bolted to the fuel injectors or engine. Both designs take excessive space, increase the weight of the engine, and are costly to make and install. Also, none of these designs attaches to or supports an electrical wiring harness for fuel injectors.
Generally, wires for transmitting electrical pulses to the fuel injectors are grouped to form a single wiring harness. When installed, the harness lays atop and aside the injectors underneath the valve cover. In these positions, the wires may be damaged or otherwise may not work properly for the life of the engine. The harness connects the wires through the engine's valve cover to an electric pulse generator and microprocessor outside the engine.
Accordingly, there is a need for a hydraulic deflector with a smaller size and with the capability to support the wiring harness away from the fuel injectors in an internal combustion engine.